.TH IP\-FOU 8 "2 Nov 2014" "iproute2" "Linux"
.SH "NAME"
ip-fou \- Foo-over-UDP receive port configuration
.P
ip-gue \- Generic UDP Encapsulation receive port configuration
.SH "SYNOPSIS"
.sp
.ad l
.in +8
.ti -8
.B ip
.RI "[ " OPTIONS " ]"
.B fou
.RI " { " COMMAND " | "
.BR help " }"
.sp
.ti -8
.BR "ip fou add"
.B port
.IR PORT
.RB "{ "
.B gue
.RI "|"
.B ipproto
.IR PROTO
.RB " }"
.RB "[ "
.B local
.IR IFADDR
.RB " ]"
.RB "[ "
.B peer
.IR IFADDR
.RB " ]"
.RB "[ "
.B peer_port
.IR PORT
.RB " ]"
.RB "[ "
.B dev
.IR IFNAME
.RB " ]"
.br
.ti -8
.BR "ip fou del"
.B port
.IR PORT
.RB "[ "
.B local
.IR IFADDR
.RB " ]"
.RB "[ "
.B peer
.IR IFADDR
.RB " ]"
.RB "[ "
.B peer_port
.IR PORT
.RB " ]"
.RB "[ "
.B dev
.IR IFNAME
.RB " ]"
.br
.ti -8
.B ip fou show
.SH DESCRIPTION
The
.B ip fou
commands are used to create and delete receive ports for Foo-over-UDP
(FOU) as well as Generic UDP Encapsulation (GUE).
.PP
Foo-over-UDP allows encapsulating packets of an IP protocol directly
over UDP. The receiver infers the protocol of a packet received on
a FOU UDP port to be the protocol configured for the port.
.PP
Generic UDP Encapsulation (GUE) encapsulates packets of an IP protocol
within UDP and an encapsulation header. The encapsulation header contains the
IP protocol number for the encapsulated packet.
.PP
When creating a FOU or GUE receive port, the port number is specified in
.I PORT
argument. If FOU is used, the IP protocol number associated with the port is specified in
.I PROTO
argument. You can bind a port to a local address/interface, by specifying the
address in the local
.I IFADDR
argument or the device in the
.I IFNAME
argument. If you would like to connect the port, you can specify the peer
address in the peer
.I IFADDR
argument and peer port in the peer_port
.I PORT
argument.
.PP
A FOU or GUE receive port is deleted by specifying
.I PORT
in the delete command, as well as local address/interface or peer address/port
(if set).
.SH EXAMPLES
.PP
.SS Configure a FOU receive port for GRE bound to 7777
.nf
# ip fou add port 7777 ipproto 47
.PP
.SS Configure a FOU receive port for IPIP bound to 8888
.nf
# ip fou add port 8888 ipproto 4
.PP
.SS Configure a GUE receive port bound to 9999
.nf
# ip fou add port 9999 gue
.PP
.SS Delete the GUE receive port bound to 9999
.nf
# ip fou del port 9999
.SS Configure a FOU receive port for GRE bound to 1.2.3.4:7777
.nf
# ip fou add port 7777 ipproto 47 local 1.2.3.4
.PP
.SH SEE ALSO
.br
.BR ip (8)
.SH AUTHOR
Tom Herbert <therbert@google.com>
